In certain surgical procedures, such as repairing fractured bones, it is necessary to attach an item, such as a plate, to a bone. For example, in repairing fractures of the facial bones or of the cranial bones, it is common to use a thin metal bone plate to hold the various pieces together. In other systems, other fasteners are used.
To use such bone plates or fasteners, holes are drilled in the various bone pieces and the bone plate or fastener is then secured to the individual bones with bone screws. Disadvantageously, this requires two steps in order to insert the screw. First, the hole must be bored in the bone. Secondly, a self-tapping bone screw is screwed into the hole. While drilling a hole significantly reduces the torque the fastener experiences during insertion, there is a significant risk that fasteners inserted with this technique establish inadequate bone/screw contact to achieve adequate connection.
Although there exists supposedly self-drilling, self-tapping fasteners and screws, it has been found that such lack adequate strength to sustain the necessary torque in such applications, or still require drilling and tapping before inserting the screw into the cranial bone.
Accordingly, there remains a need for a bone screw which can be inserted without the need for drilling or tapping. There is also a need for a bone screw which is stably inserted into the bone and which is self-drilling and self-tapping. What is further needed is a bone screw which has a very strong head to body connection so as to withstand the required torque for such insertion. The present invention fulfills these needs and provides other related advantages.